arm-ttk does not seem to recognize an outputs reference to a DropDown living inside an EditableGrid's column

**arm-ttk version:** 0.24
**Scenario:** A DropDown control inside a column in an EditableGrid control is referenced in an "outputs" parameter using the following expression (see the full CUID sample at the very bottom) that references it via a reference to the containing column's column id:
`[concat('Value: ', first(basics('EditableGrid1')).Column1)]`

**Problem:** When running arm-ttk against the example shown below, the following error is returned:
```
arm-ttk: Failed: Allowed Values Should Actually Be Allowed
Error: Could not find DropDown1 in outputs
```

**NOTE:** The same issue is also noticed when placing an OptionsGroup control inside an EditableGrid's column. But a TextBox seems to fare well though.

What are we missing here?

**Full sample CUID:**

{

  "$schema": "https://schema.management.azure.com/schemas/0.1.2-preview/CreateUIDefinition.MultiVm.json#",

  "handler": "Microsoft.Azure.CreateUIDef",

  "version": "0.1.2-preview",

  "parameters": {

    "basics": [

      {

        "ariaLabel": "EditableGrid1",

        "constraints": {

          "columns": [

            {

              "element": {

                "constraints": {

                  "allowedValues": [

                    {

                      "label": "Item1",

                      "value": "Value1"

                    },

                    {

                      "label": "Item2",

                      "value": "Value2"

                    }

                  ]

                },

                "label": "DropDown1",

                "name": "DropDown1",

                "toolTip": "DropDown1",

                "type": "Microsoft.Common.DropDown"

              },

              "header": "Column1",

              "id": "Column1",

              "width": "1fr"

            }

          ]

        },

        "label": "EditableGrid1",

        "name": "EditableGrid1",

        "type": "Microsoft.Common.EditableGrid"

      }

    ],

    "steps": [],

    "outputs": {

      "location": "[location()]",

      "EditableGrid1": "[concat('Value: ', first(basics('EditableGrid1')).Column1)]"

    }

  },

  "metadata": {

    "_generator": {

      "name": "MaestroStudio",

      "sku": "Solo",

      "version": "0.9.0.0",

      "template": {

        "author": "StratusOn",

        "id": "EA622966-CE0C-46E7-841B-73C2E6ED5DEB",

        "description": "A blank Azure Marketplace Managed Application offer."

      }

    },

    "_sync": {

      "offer": {

        "displayName": "My Offer"

      },

      "plan": {

        "displayName": "Plan"

      }

    }

  }

}